blob: caa2d51085dd95af2b846aa066c4b474483f52cc [file] [log] [blame]
use serde::ser::{self, Serialize};
use error::{Error, Result};
/// Attempts to serialize the input as a JSON5 string (actually a JSON string).
pub fn to_string<T>(value: &T) -> Result<String>
where
T: Serialize,
{
let mut serializer = Serializer {
output: String::new(),
};
value.serialize(&mut serializer)?;
Ok(serializer.output)
}
struct Serializer {
output: String,
// TODO settings for formatting (single vs double quotes, whitespace etc)
}
impl Serializer {
fn call_to_string<T>(&mut self, v: T) -> Result<()>
where
T: ToString,
{
self.output += &v.to_string();
Ok(())
}
}
impl<'a> ser::Serializer for &'a mut Serializer {
type Ok = ();
type Error = Error;
type SerializeSeq = Self;
type SerializeTuple = Self;
type SerializeTupleStruct = Self;
type SerializeTupleVariant = Self;
type SerializeMap = Self;
type SerializeStruct = Self;
type SerializeStructVariant = Self;
fn serialize_bool(self, v: bool) -> Result<()> {
self.call_to_string(v)
}
fn serialize_i8(self, v: i8) -> Result<()> {
self.call_to_string(v)
}
fn serialize_i16(self, v: i16) -> Result<()> {
self.call_to_string(v)
}
fn serialize_i32(self, v: i32) -> Result<()> {
self.call_to_string(v)
}
fn serialize_i64(self, v: i64) -> Result<()> {
self.call_to_string(v)
}
fn serialize_u8(self, v: u8) -> Result<()> {
self.call_to_string(v)
}
fn serialize_u16(self, v: u16) -> Result<()> {
self.call_to_string(v)
}
fn serialize_u32(self, v: u32) -> Result<()> {
self.call_to_string(v)
}
fn serialize_u64(self, v: u64) -> Result<()> {
self.call_to_string(v)
}
fn serialize_f32(self, v: f32) -> Result<()> {
self.call_to_string(v)
}
fn serialize_f64(self, v: f64) -> Result<()> {
self.call_to_string(v)
}
fn serialize_char(self, v: char) -> Result<()> {
self.serialize_str(&v.to_string())
}
fn serialize_str(self, v: &str) -> Result<()> {
self.output += "\"";
self.output += &escape(v);
self.output += "\"";
Ok(())
}
fn serialize_bytes(self, _v: &[u8]) -> Result<()> {
unimplemented!() // TODO
}
fn serialize_none(self) -> Result<()> {
self.serialize_unit()
}
fn serialize_some<T>(self, value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
value.serialize(self)
}
fn serialize_unit(self) -> Result<()> {
self.output += "null";
Ok(())
}
fn serialize_unit_struct(self, _name: &'static str) -> Result<()> {
self.serialize_unit()
}
fn serialize_unit_variant(
self,
_name: &'static str,
_variant_index: u32,
variant: &'static str,
) -> Result<()> {
self.serialize_str(variant)
}
fn serialize_newtype_struct<T>(self, _name: &'static str, value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
value.serialize(self)
}
fn serialize_newtype_variant<T>(
self,
_name: &'static str,
_variant_index: u32,
variant: &'static str,
value: &T,
) -> Result<()>
where
T: ?Sized + Serialize,
{
self.output += "{";
variant.serialize(&mut *self)?; // TODO drop the quotes where possible
self.output += ":";
value.serialize(&mut *self)?;
self.output += "}";
Ok(())
}
fn serialize_seq(self, _len: Option<usize>) -> Result<Self::SerializeSeq> {
self.output += "[";
Ok(self)
}
fn serialize_tuple(self, len: usize) -> Result<Self::SerializeTuple> {
self.serialize_seq(Some(len))
}
fn serialize_tuple_struct(
self,
_name: &'static str,
len: usize,
) -> Result<Self::SerializeTupleStruct> {
self.serialize_seq(Some(len))
}
fn serialize_tuple_variant(
self,
_name: &'static str,
_variant_index: u32,
variant: &'static str,
_len: usize,
) -> Result<Self::SerializeTupleVariant> {
self.output += "{";
variant.serialize(&mut *self)?;
self.output += ":[";
Ok(self)
}
fn serialize_map(self, _len: Option<usize>) -> Result<Self::SerializeMap> {
self.output += "{";
Ok(self)
}
fn serialize_struct(self, _name: &'static str, len: usize) -> Result<Self::SerializeStruct> {
self.serialize_map(Some(len))
}
fn serialize_struct_variant(
self,
_name: &'static str,
_variant_index: u32,
variant: &'static str,
_len: usize,
) -> Result<Self::SerializeStructVariant> {
self.output += "{";
variant.serialize(&mut *self)?;
self.output += ":{";
Ok(self)
}
}
impl<'a> ser::SerializeSeq for &'a mut Serializer {
type Ok = ();
type Error = Error;
fn serialize_element<T>(&mut self, value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
if !self.output.ends_with('[') {
self.output += ",";
}
value.serialize(&mut **self)
}
fn end(self) -> Result<()> {
self.output += "]";
Ok(())
}
}
impl<'a> ser::SerializeTuple for &'a mut Serializer {
type Ok = ();
type Error = Error;
fn serialize_element<T>(&mut self, value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
ser::SerializeSeq::serialize_element(self, value)
}
fn end(self) -> Result<()> {
ser::SerializeSeq::end(self)
}
}
impl<'a> ser::SerializeTupleStruct for &'a mut Serializer {
type Ok = ();
type Error = Error;
fn serialize_field<T>(&mut self, value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
ser::SerializeSeq::serialize_element(self, value)
}
fn end(self) -> Result<()> {
ser::SerializeSeq::end(self)
}
}
impl<'a> ser::SerializeTupleVariant for &'a mut Serializer {
type Ok = ();
type Error = Error;
fn serialize_field<T>(&mut self, value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
ser::SerializeSeq::serialize_element(self, value)
}
fn end(self) -> Result<()> {
self.output += "]}";
Ok(())
}
}
impl<'a> ser::SerializeMap for &'a mut Serializer {
type Ok = ();
type Error = Error;
fn serialize_key<T>(&mut self, key: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
if !self.output.ends_with('{') {
self.output += ",";
}
key.serialize(&mut **self)
}
fn serialize_value<T>(&mut self, value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
self.output += ":";
value.serialize(&mut **self)
}
fn end(self) -> Result<()> {
self.output += "}";
Ok(())
}
}
impl<'a> ser::SerializeStruct for &'a mut Serializer {
type Ok = ();
type Error = Error;
fn serialize_field<T>(&mut self, key: &'static str, value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
ser::SerializeMap::serialize_key(self, key)?;
ser::SerializeMap::serialize_value(self, value)
}
fn end(self) -> Result<()> {
ser::SerializeMap::end(self)
}
}
impl<'a> ser::SerializeStructVariant for &'a mut Serializer {
type Ok = ();
type Error = Error;
fn serialize_field<T>(&mut self, key: &'static str, value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
ser::SerializeStruct::serialize_field(self, key, value)
}
fn end(self) -> Result<()> {
self.output += "}}";
Ok(())
}
}
fn escape(v: &str) -> String {
v.chars()
.flat_map(|c| match c {
'"' => vec!['\\', c],
'\n' => vec!['\\', 'n'],
'\\' => vec!['\\', '\\'],
c => vec![c],
}).collect()
}